Doctors use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when :
Ventricular walls vibrate due to gushing in of blood from atria
Semilunar valves close down after the blood flows into vessels from ventricles
AV node receives signal from SA node
AV valves open up
As we learnt in
Lub-dub -
During each cardiac cycle two prominent sounds are produced which can be easily heard through a stethoscope.
- wherein
The first heart sound (lub) is associated with the closure of the tricuspid and bicuspid valves whereas the second heart sound (dub) is associated with the closure of the semilunar valves.
The second heart sound (dub) is associated with the closure of the similarly value.
Option 1)
Ventricular walls vibrate due to gushing in of blood from atria
Incorrect
Option 2)
Semilunar valves close down after the blood flows into vessels from ventricles
Correct
Option 3)
AV node receives signal from SA node
Incorrect
Option 4)
AV valves open up
Incorrect